Right from the first few seconds until the end, The LEGO Batman Movie is hilarious, a lot of fun, and even better than the LEGO Movie.
The story - which follows the Caped Crusader in his journey of protecting Gotham City, dealing with his new son, Dick Grayson, and...a strange bromance (or "foemance"?) with the Joker.
The jokes are constant, with numerous Batman references, slapstick, and sight gags. Not to mention, of course, the creative use of LEGOs.